The present disclosure generally relates to medical devices, systems, and methods. In particular, the present disclosure generally relates to the removal of intravascular or intracavitary thrombus or other material which may frequently require removal to restore blood flow or other normal functionality of the organ system affected.
Typically, blood clot or emboli to the pulmonary arteries of the lung, the brain, the peripheral arteries of the extremities, in the venous system, or in dialysis access vessels are potentially life and/or limb threatening conditions. These clots are typically cleared when medically indicated by either pharmacological (thrombolytic and/or anticoagulant drugs) or mechanical means or a combination of the two. Thrombolytic drugs typically require several hours to days to accomplish dissolving these clots. Frequently, there is not sufficient “warm” ischemic time for the target organ to permit such a long time to reperfusion. Thrombolytic drugs also have an approximately 5% incidence of major complications such as hemorrhage and stroke. Currently available mechanical devices may not be effective in the presence of large volumes of thrombus or may have a very large diameter and may be stiff. Thus, these devices may be difficult or impossible to advance into curved and tortuous vessels such as the pulmonary arteries. The “Hydrolyzer” devices available in the marketplace may break up a clot and suction the resulting particles out, but may infuse large volumes of fluid as part of their action. Such infusion may be physiologically difficult to handle for the patient. Other devices, like “AngioVac” may require a miniature veno-venous cardiovascular bypass to allow filtering out of the suctioned thrombus and return of the cleared blood to the patient. Most of these devices may also hemolyze blood, which may result in damage to the kidneys and may also cause distal emboli.
For these reasons, emergency open surgical thrombectomy, which in itself may have a high mortality and morbidity, is often employed as a last resort, especially for large pulmonary emboli. There are therefore needs for devices which can rapidly and safely extract large volumes of blood clot or other materials with little or no adjuvant use of thrombolytic drugs. Such devices may be used during intravascular interventions to prevent distal embolization by capture of blood clots or atheromatous material.
References which may be of interest include U.S. Pat. Nos. 8,377,092, 7,479,153, 6,494,895, and 7,976,560 and U.S. Patent Application Publication Nos. 2012/0330350 and 2012/0330346.